I've never experienced this bug with PRE since 1.3.1 or thereabouts, but anytime I try to launch a craft and PRE is enabled, my game immediately freezes. If I disable PRE in the settings config, everything works fine, until I activate PRE in the flight screen, then it freezes again.
KSP 1.8.1
PRE 1.17
I verified my files through steam and even though PRE is the only mod I have installed, it persists.